The critical reception of Lost in Yonkers has been mixed since it was first published in 1991. Part of this has to do with Simon's status as an extremely popular playwright. When a playwright—or any other writer, for that matter—sells a lot of books or performances, some critics tend to view this as a sign that the writer is not artistic. Indeed, Simon received some scathing initial reviews. In his review of the play for the New Leader, Stefan Kanfer says, "Watching Simon work with this material is like viewing Bob Vila on reruns of This Old House.'' Kanfer also notes that Simon's goal is ‘‘To please ticketholders'' and that he does this by creating "a situation tragedy'' and covering it "in pastel shades.'' Kanfer was not alone in the negative comments. In her review of the play for the New Yorker, Mimi Kramer says that some of the characters are "phony'' and notes that the play "seems to suffer from a basic confusion about what sorts of things are interesting as truth and what sorts of things are interesting as fiction.’’

However, Simon also had his champions when the play was initially reviewed. In the New York Times Magazine, David Richards calls Simon ‘‘the last Broadway playwright,’’ indicating that all of the other great Broadway playwrights are gone. Richards does note that Simon "insists—a bit disingenuously—that there is nothing autobiographical about Lost in Yonkers,'' though Richards sees clear autobiographical links. Other positive comments include the review by James S. Torrens in America. Torrens notes that "Lost in Yonkers touches all the chords.’’

In the decade since the play was first published, Simon's reputation in general, and the reputation of Lost in Yonkers in particular, has received favorable criticism. As J. Ellen Gainor notes in her 1996 entry on Simon for American Writers, when Simon won the Pulitzer Prize for Lost in Yonkers, "a strategic shift took place in the critical reception of his work. Critics began to take a tone of more uniform praise.'' Finally, as Susan Koprince notes of Lost in Yonkers in her 2002 entry on Simon for the Dictionary of Literary Biography, ultimately, the play has become ‘‘Both a critical and popular success.’’ Koprince also says that the play ‘‘represents Simon at the pinnacle of his career.''